@gebjeff There is no harm in trying - just the cost of the splitter. It simply boils down to the power being generated being sufficient to put enough to both cameras for charging. Here's a review on Amazon with someone doing exactly what you want:

https://www.amazon.com/dp/B08GFNXFXZ

Nicholas

5.0 out of 5 stars Works for power splitting.

Reviewed in the United States on May 7, 2021

Verified Purchase

I use this to charge my two cameras and it works perfect.

I have a solar panel with a single micro usb cable as its only output, I use this along with two 10ft micro usb M-F cables to charge the batteries in my outdoor cameras. It works perfectly; both my cameras stay charged.

I wrapped the connection point with electrical tape to waterproof it I don't know if it is needed, but I like to play it safe. I'm looking into a better solution but Its protecting it from the elements for now.

Will update if anything happens to the cables.